This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. The goal of these experiments is to determine if relatively short exposure to a cellulose sulfate microbide enhances the susceptibility to vaginal SIV inoculation.